In order to attach a femoral component of a leg bone during re-surfacing in hip surgery, the femoral bone is prepared such that it obtains a specific shape. While preparing the femoral bone, it is desirable to avoid any kind of notching or weakening of the joint neck, since such weakening or notching can cause cracks or fractures.
A femoral implant component has a symmetrical inner shape with a central pin, and it is desirable to accurately define and realize the position and orientation of the hole for this central pin. During the re-surfacing treatment, a pilot drill hole is made for the central pin of the implant, and it is similarly desirable to place the pilot drill hole as accurately as possible, since all the subsequent working steps are based on this location.
In order to support this drilling process, various tools have been used to define the entry point and the axis for the drill hole. U.S. Pat. No. 6,156,069 discloses a gripping device which grips the femoral neck and can guide the drill. U.S. Pat. No. 6,595,999 B2 discloses a drill mounting attached as a frame, in which a probe is provided in order to ensure positioning. Directing fastening to the femoral head or to a plane face of the femoral head, following a milling procedure, is also known from U.S. Pat. No. 6,595,999 B2.